From 8ee3991715c3090360c0b7ceea64adaf48a8f2cc Mon Sep 17 00:00:00 2001
From: Bryant Biggs <bryantbiggs@gmail.com>
Date: Tue, 11 Jan 2022 15:16:51 -0500
Subject: [PATCH] fix: correct `for_each` map on VPC endpoints to propagate
 endpoint maps correctly

---
 examples/complete-vpc/README.md |   1 +
 examples/complete-vpc/main.tf   |  19 +++
 modules/vpc-endpoints/main.tf   |   8 +-
 outputs.tf                      | 202 ++++++++++++++++----------------
 4 files changed, 123 insertions(+), 107 deletions(-)

diff --git a/examples/complete-vpc/README.md b/examples/complete-vpc/README.md
index 25ee27547..4a1b1a730 100644
--- a/examples/complete-vpc/README.md
+++ b/examples/complete-vpc/README.md
@@ -42,6 +42,7 @@ Note that this example may create resources which can cost money (AWS Elastic IP
 
 | Name | Type |
 |------|------|
+| [aws_security_group.vpc_tls](https://registry.terraform.io/providers/hashicorp/aws/latest/docs/resources/security_group) | resource |
 | [aws_iam_policy_document.dynamodb_endpoint_policy](https://registry.terraform.io/providers/hashicorp/aws/latest/docs/data-sources/iam_policy_document) | data source |
 | [aws_iam_policy_document.generic_endpoint_policy](https://registry.terraform.io/providers/hashicorp/aws/latest/docs/data-sources/iam_policy_document) | data source |
 | [aws_security_group.default](https://registry.terraform.io/providers/hashicorp/aws/latest/docs/data-sources/security_group) | data source |
diff --git a/examples/complete-vpc/main.tf b/examples/complete-vpc/main.tf
index 6ce367f7b..1dfbb55bf 100644
--- a/examples/complete-vpc/main.tf
+++ b/examples/complete-vpc/main.tf
@@ -102,6 +102,7 @@ module "vpc_endpoints" {
       service             = "ssm"
       private_dns_enabled = true
       subnet_ids          = module.vpc.private_subnets
+      security_group_ids  = [aws_security_group.vpc_tls.id]
     },
     ssmmessages = {
       service             = "ssmmessages"
@@ -127,6 +128,7 @@ module "vpc_endpoints" {
       service             = "ec2"
       private_dns_enabled = true
       subnet_ids          = module.vpc.private_subnets
+      security_group_ids  = [aws_security_group.vpc_tls.id]
     },
     ec2messages = {
       service             = "ec2messages"
@@ -149,6 +151,7 @@ module "vpc_endpoints" {
       service             = "kms"
       private_dns_enabled = true
       subnet_ids          = module.vpc.private_subnets
+      security_group_ids  = [aws_security_group.vpc_tls.id]
     },
     codedeploy = {
       service             = "codedeploy"
@@ -232,3 +235,19 @@ data "aws_iam_policy_document" "generic_endpoint_policy" {
     }
   }
 }
+
+resource "aws_security_group" "vpc_tls" {
+  name_prefix = "${local.name}-vpc_tls"
+  description = "Allow TLS inbound traffic"
+  vpc_id      = module.vpc.vpc_id
+
+  ingress {
+    description = "TLS from VPC"
+    from_port   = 443
+    to_port     = 443
+    protocol    = "tcp"
+    cidr_blocks = [module.vpc.vpc_cidr_block]
+  }
+
+  tags = local.tags
+}
diff --git a/modules/vpc-endpoints/main.tf b/modules/vpc-endpoints/main.tf
index 58b3270ee..a8cc85530 100644
--- a/modules/vpc-endpoints/main.tf
+++ b/modules/vpc-endpoints/main.tf
@@ -1,13 +1,9 @@
-locals {
-  endpoints = var.create ? var.endpoints : tomap({})
-}
-
 ################################################################################
 # Endpoint(s)
 ################################################################################
 
 data "aws_vpc_endpoint_service" "this" {
-  for_each = local.endpoints
+  for_each = { for k, v in var.endpoints : k => v if var.create }
 
   service      = lookup(each.value, "service", null)
   service_name = lookup(each.value, "service_name", null)
@@ -19,7 +15,7 @@ data "aws_vpc_endpoint_service" "this" {
 }
 
 resource "aws_vpc_endpoint" "this" {
-  for_each = local.endpoints
+  for_each = { for k, v in var.endpoints : k => v if var.create }
 
   vpc_id            = var.vpc_id
   service_name      = data.aws_vpc_endpoint_service.this[each.key].service_name
diff --git a/outputs.tf b/outputs.tf
index 064be15fb..8e762d673 100644
--- a/outputs.tf
+++ b/outputs.tf
@@ -1,371 +1,371 @@
 output "vpc_id" {
   description = "The ID of the VPC"
-  value       = concat(aws_vpc.this.*.id, [""])[0]
+  value       = try(aws_vpc.this[0].id, "")
 }
 
 output "vpc_arn" {
   description = "The ARN of the VPC"
-  value       = concat(aws_vpc.this.*.arn, [""])[0]
+  value       = try(aws_vpc.this[0].arn, "")
 }
 
 output "vpc_cidr_block" {
   description = "The CIDR block of the VPC"
-  value       = concat(aws_vpc.this.*.cidr_block, [""])[0]
+  value       = try(aws_vpc.this[0].cidr_block, "")
 }
 
 output "default_security_group_id" {
   description = "The ID of the security group created by default on VPC creation"
-  value       = concat(aws_vpc.this.*.default_security_group_id, [""])[0]
+  value       = try(aws_vpc.this[0].default_security_group_id, "")
 }
 
 output "default_network_acl_id" {
   description = "The ID of the default network ACL"
-  value       = concat(aws_vpc.this.*.default_network_acl_id, [""])[0]
+  value       = try(aws_vpc.this[0].default_network_acl_id, "")
 }
 
 output "default_route_table_id" {
   description = "The ID of the default route table"
-  value       = concat(aws_vpc.this.*.default_route_table_id, [""])[0]
+  value       = try(aws_vpc.this[0].default_route_table_id, "")
 }
 
 output "vpc_instance_tenancy" {
   description = "Tenancy of instances spin up within VPC"
-  value       = concat(aws_vpc.this.*.instance_tenancy, [""])[0]
+  value       = try(aws_vpc.this[0].instance_tenancy, "")
 }
 
 output "vpc_enable_dns_support" {
   description = "Whether or not the VPC has DNS support"
-  value       = concat(aws_vpc.this.*.enable_dns_support, [""])[0]
+  value       = try(aws_vpc.this[0].enable_dns_support, "")
 }
 
 output "vpc_enable_dns_hostnames" {
   description = "Whether or not the VPC has DNS hostname support"
-  value       = concat(aws_vpc.this.*.enable_dns_hostnames, [""])[0]
+  value       = try(aws_vpc.this[0].enable_dns_hostnames, "")
 }
 
 output "vpc_main_route_table_id" {
   description = "The ID of the main route table associated with this VPC"
-  value       = concat(aws_vpc.this.*.main_route_table_id, [""])[0]
+  value       = try(aws_vpc.this[0].main_route_table_id, "")
 }
 
 output "vpc_ipv6_association_id" {
   description = "The association ID for the IPv6 CIDR block"
-  value       = concat(aws_vpc.this.*.ipv6_association_id, [""])[0]
+  value       = try(aws_vpc.this[0].ipv6_association_id, "")
 }
 
 output "vpc_ipv6_cidr_block" {
   description = "The IPv6 CIDR block"
-  value       = concat(aws_vpc.this.*.ipv6_cidr_block, [""])[0]
+  value       = try(aws_vpc.this[0].ipv6_cidr_block, "")
 }
 
 output "vpc_secondary_cidr_blocks" {
   description = "List of secondary CIDR blocks of the VPC"
-  value       = aws_vpc_ipv4_cidr_block_association.this.*.cidr_block
+  value       = aws_vpc_ipv4_cidr_block_association.this[*].cidr_block
 }
 
 output "vpc_owner_id" {
   description = "The ID of the AWS account that owns the VPC"
-  value       = concat(aws_vpc.this.*.owner_id, [""])[0]
+  value       = try(aws_vpc.this[0].owner_id, "")
 }
 
 output "private_subnets" {
   description = "List of IDs of private subnets"
-  value       = aws_subnet.private.*.id
+  value       = aws_subnet.private[*].id
 }
 
 output "private_subnet_arns" {
   description = "List of ARNs of private subnets"
-  value       = aws_subnet.private.*.arn
+  value       = aws_subnet.private[*].arn
 }
 
 output "private_subnets_cidr_blocks" {
   description = "List of cidr_blocks of private subnets"
-  value       = aws_subnet.private.*.cidr_block
+  value       = aws_subnet.private[*].cidr_block
 }
 
 output "private_subnets_ipv6_cidr_blocks" {
   description = "List of IPv6 cidr_blocks of private subnets in an IPv6 enabled VPC"
-  value       = aws_subnet.private.*.ipv6_cidr_block
+  value       = aws_subnet.private[*].ipv6_cidr_block
 }
 
 output "public_subnets" {
   description = "List of IDs of public subnets"
-  value       = aws_subnet.public.*.id
+  value       = aws_subnet.public[*].id
 }
 
 output "public_subnet_arns" {
   description = "List of ARNs of public subnets"
-  value       = aws_subnet.public.*.arn
+  value       = aws_subnet.public[*].arn
 }
 
 output "public_subnets_cidr_blocks" {
   description = "List of cidr_blocks of public subnets"
-  value       = aws_subnet.public.*.cidr_block
+  value       = aws_subnet.public[*].cidr_block
 }
 
 output "public_subnets_ipv6_cidr_blocks" {
   description = "List of IPv6 cidr_blocks of public subnets in an IPv6 enabled VPC"
-  value       = aws_subnet.public.*.ipv6_cidr_block
+  value       = aws_subnet.public[*].ipv6_cidr_block
 }
 
 output "outpost_subnets" {
   description = "List of IDs of outpost subnets"
-  value       = aws_subnet.outpost.*.id
+  value       = aws_subnet.outpost[*].id
 }
 
 output "outpost_subnet_arns" {
   description = "List of ARNs of outpost subnets"
-  value       = aws_subnet.outpost.*.arn
+  value       = aws_subnet.outpost[*].arn
 }
 
 output "outpost_subnets_cidr_blocks" {
   description = "List of cidr_blocks of outpost subnets"
-  value       = aws_subnet.outpost.*.cidr_block
+  value       = aws_subnet.outpost[*].cidr_block
 }
 
 output "outpost_subnets_ipv6_cidr_blocks" {
   description = "List of IPv6 cidr_blocks of outpost subnets in an IPv6 enabled VPC"
-  value       = aws_subnet.outpost.*.ipv6_cidr_block
+  value       = aws_subnet.outpost[*].ipv6_cidr_block
 }
 
 output "database_subnets" {
   description = "List of IDs of database subnets"
-  value       = aws_subnet.database.*.id
+  value       = aws_subnet.database[*].id
 }
 
 output "database_subnet_arns" {
   description = "List of ARNs of database subnets"
-  value       = aws_subnet.database.*.arn
+  value       = aws_subnet.database[*].arn
 }
 
 output "database_subnets_cidr_blocks" {
   description = "List of cidr_blocks of database subnets"
-  value       = aws_subnet.database.*.cidr_block
+  value       = aws_subnet.database[*].cidr_block
 }
 
 output "database_subnets_ipv6_cidr_blocks" {
   description = "List of IPv6 cidr_blocks of database subnets in an IPv6 enabled VPC"
-  value       = aws_subnet.database.*.ipv6_cidr_block
+  value       = aws_subnet.database[*].ipv6_cidr_block
 }
 
 output "database_subnet_group" {
   description = "ID of database subnet group"
-  value       = concat(aws_db_subnet_group.database.*.id, [""])[0]
+  value       = try(aws_db_subnet_group.database[0].id, "")
 }
 
 output "database_subnet_group_name" {
   description = "Name of database subnet group"
-  value       = concat(aws_db_subnet_group.database.*.name, [""])[0]
+  value       = try(aws_db_subnet_group.database[0].name, "")
 }
 
 output "redshift_subnets" {
   description = "List of IDs of redshift subnets"
-  value       = aws_subnet.redshift.*.id
+  value       = aws_subnet.redshift[*].id
 }
 
 output "redshift_subnet_arns" {
   description = "List of ARNs of redshift subnets"
-  value       = aws_subnet.redshift.*.arn
+  value       = aws_subnet.redshift[*].arn
 }
 
 output "redshift_subnets_cidr_blocks" {
   description = "List of cidr_blocks of redshift subnets"
-  value       = aws_subnet.redshift.*.cidr_block
+  value       = aws_subnet.redshift[*].cidr_block
 }
 
 output "redshift_subnets_ipv6_cidr_blocks" {
   description = "List of IPv6 cidr_blocks of redshift subnets in an IPv6 enabled VPC"
-  value       = aws_subnet.redshift.*.ipv6_cidr_block
+  value       = aws_subnet.redshift[*].ipv6_cidr_block
 }
 
 output "redshift_subnet_group" {
   description = "ID of redshift subnet group"
-  value       = concat(aws_redshift_subnet_group.redshift.*.id, [""])[0]
+  value       = try(aws_redshift_subnet_group.redshift[0].id, "")
 }
 
 output "elasticache_subnets" {
   description = "List of IDs of elasticache subnets"
-  value       = aws_subnet.elasticache.*.id
+  value       = aws_subnet.elasticache[*].id
 }
 
 output "elasticache_subnet_arns" {
   description = "List of ARNs of elasticache subnets"
-  value       = aws_subnet.elasticache.*.arn
+  value       = aws_subnet.elasticache[*].arn
 }
 
 output "elasticache_subnets_cidr_blocks" {
   description = "List of cidr_blocks of elasticache subnets"
-  value       = aws_subnet.elasticache.*.cidr_block
+  value       = aws_subnet.elasticache[*].cidr_block
 }
 
 output "elasticache_subnets_ipv6_cidr_blocks" {
   description = "List of IPv6 cidr_blocks of elasticache subnets in an IPv6 enabled VPC"
-  value       = aws_subnet.elasticache.*.ipv6_cidr_block
+  value       = aws_subnet.elasticache[*].ipv6_cidr_block
 }
 
 output "intra_subnets" {
   description = "List of IDs of intra subnets"
-  value       = aws_subnet.intra.*.id
+  value       = aws_subnet.intra[*].id
 }
 
 output "intra_subnet_arns" {
   description = "List of ARNs of intra subnets"
-  value       = aws_subnet.intra.*.arn
+  value       = aws_subnet.intra[*].arn
 }
 
 output "intra_subnets_cidr_blocks" {
   description = "List of cidr_blocks of intra subnets"
-  value       = aws_subnet.intra.*.cidr_block
+  value       = aws_subnet.intra[*].cidr_block
 }
 
 output "intra_subnets_ipv6_cidr_blocks" {
   description = "List of IPv6 cidr_blocks of intra subnets in an IPv6 enabled VPC"
-  value       = aws_subnet.intra.*.ipv6_cidr_block
+  value       = aws_subnet.intra[*].ipv6_cidr_block
 }
 
 output "elasticache_subnet_group" {
   description = "ID of elasticache subnet group"
-  value       = concat(aws_elasticache_subnet_group.elasticache.*.id, [""])[0]
+  value       = try(aws_elasticache_subnet_group.elasticache[0].id, "")
 }
 
 output "elasticache_subnet_group_name" {
   description = "Name of elasticache subnet group"
-  value       = concat(aws_elasticache_subnet_group.elasticache.*.name, [""])[0]
+  value       = try(aws_elasticache_subnet_group.elasticache[0].name, "")
 }
 
 output "public_route_table_ids" {
   description = "List of IDs of public route tables"
-  value       = aws_route_table.public.*.id
+  value       = aws_route_table.public[*].id
 }
 
 output "private_route_table_ids" {
   description = "List of IDs of private route tables"
-  value       = aws_route_table.private.*.id
+  value       = aws_route_table.private[*].id
 }
 
 output "database_route_table_ids" {
   description = "List of IDs of database route tables"
-  value       = length(aws_route_table.database.*.id) > 0 ? aws_route_table.database.*.id : aws_route_table.private.*.id
+  value       = try(coalescelist(aws_route_table.database[*].id, aws_route_table.private[*].id), [])
 }
 
 output "redshift_route_table_ids" {
   description = "List of IDs of redshift route tables"
-  value       = length(aws_route_table.redshift.*.id) > 0 ? aws_route_table.redshift.*.id : (var.enable_public_redshift ? aws_route_table.public.*.id : aws_route_table.private.*.id)
+  value       = try(coalescelist(aws_route_table.redshift[*].id, aws_route_table.public[*].id, aws_route_table.private[*].id), [])
 }
 
 output "elasticache_route_table_ids" {
   description = "List of IDs of elasticache route tables"
-  value       = length(aws_route_table.elasticache.*.id) > 0 ? aws_route_table.elasticache.*.id : aws_route_table.private.*.id
+  value       = try(coalescelist(aws_route_table.elasticache[*].id, aws_route_table.private[*].id), [])
 }
 
 output "intra_route_table_ids" {
   description = "List of IDs of intra route tables"
-  value       = aws_route_table.intra.*.id
+  value       = aws_route_table.intra[*].id
 }
 
 output "public_internet_gateway_route_id" {
   description = "ID of the internet gateway route."
-  value       = concat(aws_route.public_internet_gateway.*.id, [""])[0]
+  value       = try(aws_route.public_internet_gateway[0].id, "")
 }
 
 output "public_internet_gateway_ipv6_route_id" {
   description = "ID of the IPv6 internet gateway route."
-  value       = concat(aws_route.public_internet_gateway_ipv6.*.id, [""])[0]
+  value       = try(aws_route.public_internet_gateway_ipv6[0].id, "")
 }
 
 output "database_internet_gateway_route_id" {
   description = "ID of the database internet gateway route."
-  value       = concat(aws_route.database_internet_gateway.*.id, [""])[0]
+  value       = try(aws_route.database_internet_gateway[0].id, "")
 }
 
 output "database_nat_gateway_route_ids" {
   description = "List of IDs of the database nat gateway route."
-  value       = aws_route.database_nat_gateway.*.id
+  value       = aws_route.database_nat_gateway[*].id
 }
 
 output "database_ipv6_egress_route_id" {
   description = "ID of the database IPv6 egress route."
-  value       = concat(aws_route.database_ipv6_egress.*.id, [""])[0]
+  value       = try(aws_route.database_ipv6_egress[0].id, "")
 }
 
 output "private_nat_gateway_route_ids" {
   description = "List of IDs of the private nat gateway route."
-  value       = aws_route.private_nat_gateway.*.id
+  value       = aws_route.private_nat_gateway[*].id
 }
 
 output "private_ipv6_egress_route_ids" {
   description = "List of IDs of the ipv6 egress route."
-  value       = aws_route.private_ipv6_egress.*.id
+  value       = aws_route.private_ipv6_egress[*].id
 }
 
 output "private_route_table_association_ids" {
   description = "List of IDs of the private route table association"
-  value       = aws_route_table_association.private.*.id
+  value       = aws_route_table_association.private[*].id
 }
 
 output "database_route_table_association_ids" {
   description = "List of IDs of the database route table association"
-  value       = aws_route_table_association.database.*.id
+  value       = aws_route_table_association.database[*].id
 }
 
 output "redshift_route_table_association_ids" {
   description = "List of IDs of the redshift route table association"
-  value       = aws_route_table_association.redshift.*.id
+  value       = aws_route_table_association.redshift[*].id
 }
 
 output "redshift_public_route_table_association_ids" {
   description = "List of IDs of the public redshidt route table association"
-  value       = aws_route_table_association.redshift_public.*.id
+  value       = aws_route_table_association.redshift_public[*].id
 }
 
 output "elasticache_route_table_association_ids" {
   description = "List of IDs of the elasticache route table association"
-  value       = aws_route_table_association.elasticache.*.id
+  value       = aws_route_table_association.elasticache[*].id
 }
 
 output "intra_route_table_association_ids" {
   description = "List of IDs of the intra route table association"
-  value       = aws_route_table_association.intra.*.id
+  value       = aws_route_table_association.intra[*].id
 }
 
 output "public_route_table_association_ids" {
   description = "List of IDs of the public route table association"
-  value       = aws_route_table_association.public.*.id
+  value       = aws_route_table_association.public[*].id
 }
 
 output "dhcp_options_id" {
   description = "The ID of the DHCP options"
-  value       = concat(aws_vpc_dhcp_options.this.*.id, [""])[0]
+  value       = try(aws_vpc_dhcp_options.this[0].id, "")
 }
 
 output "nat_ids" {
   description = "List of allocation ID of Elastic IPs created for AWS NAT Gateway"
-  value       = aws_eip.nat.*.id
+  value       = aws_eip.nat[*].id
 }
 
 output "nat_public_ips" {
   description = "List of public Elastic IPs created for AWS NAT Gateway"
-  value       = var.reuse_nat_ips ? var.external_nat_ips : aws_eip.nat.*.public_ip
+  value       = var.reuse_nat_ips ? var.external_nat_ips : aws_eip.nat[*].public_ip
 }
 
 output "natgw_ids" {
   description = "List of NAT Gateway IDs"
-  value       = aws_nat_gateway.this.*.id
+  value       = aws_nat_gateway.this[*].id
 }
 
 output "igw_id" {
   description = "The ID of the Internet Gateway"
-  value       = concat(aws_internet_gateway.this.*.id, [""])[0]
+  value       = try(aws_internet_gateway.this[0].id, "")
 }
 
 output "igw_arn" {
   description = "The ARN of the Internet Gateway"
-  value       = concat(aws_internet_gateway.this.*.arn, [""])[0]
+  value       = try(aws_internet_gateway.this[0].arn, "")
 }
 
 output "egress_only_internet_gateway_id" {
   description = "The ID of the egress only Internet Gateway"
-  value       = concat(aws_egress_only_internet_gateway.this.*.id, [""])[0]
+  value       = try(aws_egress_only_internet_gateway.this[0].id, "")
 }
 
 output "cgw_ids" {
@@ -385,138 +385,138 @@ output "this_customer_gateway" {
 
 output "vgw_id" {
   description = "The ID of the VPN Gateway"
-  value       = concat(aws_vpn_gateway.this.*.id, aws_vpn_gateway_attachment.this.*.vpn_gateway_id, [""])[0]
+  value       = try(aws_vpn_gateway.this[0].id, aws_vpn_gateway_attachment.this[0].vpn_gateway_id, "")
 }
 
 output "vgw_arn" {
   description = "The ARN of the VPN Gateway"
-  value       = concat(aws_vpn_gateway.this.*.arn, [""])[0]
+  value       = try(aws_vpn_gateway.this[0].arn, "")
 }
 
 output "default_vpc_id" {
   description = "The ID of the Default VPC"
-  value       = concat(aws_default_vpc.this.*.id, [""])[0]
+  value       = try(aws_default_vpc.this[0].id, "")
 }
 
 output "default_vpc_arn" {
   description = "The ARN of the Default VPC"
-  value       = concat(aws_default_vpc.this.*.arn, [""])[0]
+  value       = try(aws_default_vpc.this[0].arn, "")
 }
 
 output "default_vpc_cidr_block" {
   description = "The CIDR block of the Default VPC"
-  value       = concat(aws_default_vpc.this.*.cidr_block, [""])[0]
+  value       = try(aws_default_vpc.this[0].cidr_block, "")
 }
 
 output "default_vpc_default_security_group_id" {
   description = "The ID of the security group created by default on Default VPC creation"
-  value       = concat(aws_default_vpc.this.*.default_security_group_id, [""])[0]
+  value       = try(aws_default_vpc.this[0].default_security_group_id, "")
 }
 
 output "default_vpc_default_network_acl_id" {
   description = "The ID of the default network ACL of the Default VPC"
-  value       = concat(aws_default_vpc.this.*.default_network_acl_id, [""])[0]
+  value       = try(aws_default_vpc.this[0].default_network_acl_id, "")
 }
 
 output "default_vpc_default_route_table_id" {
   description = "The ID of the default route table of the Default VPC"
-  value       = concat(aws_default_vpc.this.*.default_route_table_id, [""])[0]
+  value       = try(aws_default_vpc.this[0].default_route_table_id, "")
 }
 
 output "default_vpc_instance_tenancy" {
   description = "Tenancy of instances spin up within Default VPC"
-  value       = concat(aws_default_vpc.this.*.instance_tenancy, [""])[0]
+  value       = try(aws_default_vpc.this[0].instance_tenancy, "")
 }
 
 output "default_vpc_enable_dns_support" {
   description = "Whether or not the Default VPC has DNS support"
-  value       = concat(aws_default_vpc.this.*.enable_dns_support, [""])[0]
+  value       = try(aws_default_vpc.this[0].enable_dns_support, "")
 }
 
 output "default_vpc_enable_dns_hostnames" {
   description = "Whether or not the Default VPC has DNS hostname support"
-  value       = concat(aws_default_vpc.this.*.enable_dns_hostnames, [""])[0]
+  value       = try(aws_default_vpc.this[0].enable_dns_hostnames, "")
 }
 
 output "default_vpc_main_route_table_id" {
   description = "The ID of the main route table associated with the Default VPC"
-  value       = concat(aws_default_vpc.this.*.main_route_table_id, [""])[0]
+  value       = try(aws_default_vpc.this[0].main_route_table_id, "")
 }
 
 output "public_network_acl_id" {
   description = "ID of the public network ACL"
-  value       = concat(aws_network_acl.public.*.id, [""])[0]
+  value       = try(aws_network_acl.public[0].id, "")
 }
 
 output "public_network_acl_arn" {
   description = "ARN of the public network ACL"
-  value       = concat(aws_network_acl.public.*.arn, [""])[0]
+  value       = try(aws_network_acl.public[0].arn, "")
 }
 
 output "private_network_acl_id" {
   description = "ID of the private network ACL"
-  value       = concat(aws_network_acl.private.*.id, [""])[0]
+  value       = try(aws_network_acl.private[0].id, "")
 }
 
 output "private_network_acl_arn" {
   description = "ARN of the private network ACL"
-  value       = concat(aws_network_acl.private.*.arn, [""])[0]
+  value       = try(aws_network_acl.private[0].arn, "")
 }
 
 output "outpost_network_acl_id" {
   description = "ID of the outpost network ACL"
-  value       = concat(aws_network_acl.outpost.*.id, [""])[0]
+  value       = try(aws_network_acl.outpost[0].id, "")
 }
 
 output "outpost_network_acl_arn" {
   description = "ARN of the outpost network ACL"
-  value       = concat(aws_network_acl.outpost.*.arn, [""])[0]
+  value       = try(aws_network_acl.outpost[0].arn, "")
 }
 
 output "intra_network_acl_id" {
   description = "ID of the intra network ACL"
-  value       = concat(aws_network_acl.intra.*.id, [""])[0]
+  value       = try(aws_network_acl.intra[0].id, "")
 }
 
 output "intra_network_acl_arn" {
   description = "ARN of the intra network ACL"
-  value       = concat(aws_network_acl.intra.*.arn, [""])[0]
+  value       = try(aws_network_acl.intra[0].arn, "")
 }
 
 output "database_network_acl_id" {
   description = "ID of the database network ACL"
-  value       = concat(aws_network_acl.database.*.id, [""])[0]
+  value       = try(aws_network_acl.database[0].id, "")
 }
 
 output "database_network_acl_arn" {
   description = "ARN of the database network ACL"
-  value       = concat(aws_network_acl.database.*.arn, [""])[0]
+  value       = try(aws_network_acl.database[0].arn, "")
 }
 
 output "redshift_network_acl_id" {
   description = "ID of the redshift network ACL"
-  value       = concat(aws_network_acl.redshift.*.id, [""])[0]
+  value       = try(aws_network_acl.redshift[0].id, "")
 }
 
 output "redshift_network_acl_arn" {
   description = "ARN of the redshift network ACL"
-  value       = concat(aws_network_acl.redshift.*.arn, [""])[0]
+  value       = try(aws_network_acl.redshift[0].arn, "")
 }
 
 output "elasticache_network_acl_id" {
   description = "ID of the elasticache network ACL"
-  value       = concat(aws_network_acl.elasticache.*.id, [""])[0]
+  value       = try(aws_network_acl.elasticache[0].id, "")
 }
 
 output "elasticache_network_acl_arn" {
   description = "ARN of the elasticache network ACL"
-  value       = concat(aws_network_acl.elasticache.*.arn, [""])[0]
+  value       = try(aws_network_acl.elasticache[0].arn, "")
 }
 
 # VPC flow log
 output "vpc_flow_log_id" {
   description = "The ID of the Flow Log resource"
-  value       = concat(aws_flow_log.this.*.id, [""])[0]
+  value       = try(aws_flow_log.this[0].id, "")
 }
 
 output "vpc_flow_log_destination_arn" {